• Title/Summary/Keyword: Cross-adaptive response

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Effects of Inhibitors on Cross-Adaptive Response to Ultraviolet Radiation or Ethyl methanesulfonate in Chinese Hamster Ovary Cells

  • Lee, Dong-Wook;Shin, Eun-Joo;Kim, Seon-Young;Um, Kyung-Il
    • Environmental Mutagens and Carcinogens
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    • v.16 no.2
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    • pp.83-87
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    • 1996
  • This study was performed by the sister chromatid exchanges (SCEs) to investigate the effects of Aphidicolin (APC) or 2, 4-dinitrophenoi (DNP) on cross-adaptive response to ultraviolet radiation (UV) or ethyl methanesulfonate (EMS) in Chinese hamster ovary (CHO) cells. The pretreatment with 1 J/m$^2$ UV decreased the yield of SCEs induced by subsequent treatment with 8 mM EMS in CHO cells. And the treatment with 10 $\mu$g/ml APC or 50 $\mu$M DNP during incubation after pretreatment with 1 J/m$^2$ UV increased the yield of SCEs induced by 8 mM EMS. The pretreatment with 2 mM EMS decreased the yield of SCEs induced by subsequent treatment with 5 J/m$^2$ UV. The treatment with 10 $\mu$g/ml APC during incubation after 2 mM EMS increased the yield of SCEs induced by 5 J/m$^2$ UV. These results suggest that APC and DNP inhibit cross-adaptive response to pretreatment with UV and subsequent treatment with EMS, and also cross-adaptive response to pretreatment with EMS and subsequent treatment with UV is inhibited by APC in CHO cells.

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Low-dose of Ultraviolet radiation-, Ethyl methanesulfonateor Bleomycin-lnduced Adaptive Response in Chinese hamster ovary Cells

  • Lee, Dong-Wook;Shin, Eun-Joo;Um, Kyung-Il
    • Environmental Mutagens and Carcinogens
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    • v.15 no.2
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    • pp.94-99
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    • 1995
  • The adaptive response and cross-adaptive response to sister chromatid exchanges (SCEs) and DNA single-strand breaks (SSBs) in Chinese hamster ovary (CHO)-K$_1$ cells treated with ultraviolet radiation (UV), ethyl methanesuffonate (EMS), or bleomycin (BLM) were investigated. Two assays were used in this study; SCEs and alkaline elution. The pretreatment with low conditioning dose of 2 mM EMS or 1 J/m$^2$ UV decreased the yield of SCEs induced by subsequent treatment with 8 mM EMS, 5 J/m$^2$ UV or 5 $\mu$g/ml BLM. And the pretreatment with low conditioning dose of 1 $\mu$g/ml BLM decreased the yield of SCEs induced by subsequent treatment with 5 $\mu$g/ml BLM or 5 J/m$^2$ UV. The rejoining of DNA SSBs in cells subsequently treated with 2 J/m$^2$ UV, 50 mM EMS or 400 $\mu$g/ml BLM is higher than that only treated with 2 J/m$^2$ UV, 50 mM EMS or 400 $\mu$g/ml BLM. These results suggest that there are the adaptive response and cross-adaptive response to SCEs, and is the adaptive response to the rejoining of DNA SSBs in CHO cells.

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Adaptive Response in CHO Cells by Bleomycin, Mitomycin C and Cadmium (Bleomycin, Mitomycin C 및 Cadmium에 의한 CHO 세포의 적응반응)

  • 김양지;한정호;정해원
    • Journal of Environmental Health Sciences
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    • v.18 no.2
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    • pp.117-124
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    • 1992
  • Pretreatment with low concentration of Bleomycin and Cadmium rendered Chinese Hamster Ovary Cells more resistant to the induction of chromosome aberration by subsequent high concentration of same agent, however Mitomycin C did not function in that way. The cells pre-exposed to low dose of Cadmitim did not show cross-resistance to challenge dose of Mitomycin C for the induction of chromosome aberration, but cells pre-exposed to Bleomycin showed cross resistance. And the cells pre-exposed to low dose of Mitomycin C showed cross resistance to challenge of Bleomycin, but Cadmium did not.

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Adaptive Robust Regression for Censored Data (중도 절단된 자료에 대한 적은 로버스트 회귀)

  • Kim, Chul-Ki
    • Journal of Korean Society for Quality Management
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    • v.27 no.2
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    • pp.112-125
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    • 1999
  • In a robust regression model, it is typically assumed that the errors are normally distributed. However, what if the error distribution is deviated from the normality and the response variables are not completely observable due to censoring? For complete data, Kim and Lai(1998) suggested a new adaptive M-estimator with an asymptotically efficient score function. The adaptive M-estimator is based on using B-splines to estimate the score function and simple cross validation to determine the knots of the B-splines, which are a modified version of Kun( 1992). We herein extend this method to right-censored data and study how well the adaptive M-estimator performs for various error distributions and censoring rates. Some impressive simulation results are shown.

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Tracking control for multi-axis system using two-degrees-of-freedom controller

  • Park, Ho-Joon;Lee, Je-Hee;Huh, Uk-Youl
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10a
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    • pp.380-384
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    • 1996
  • This paper represents an adaptive position controller with the disturbance observer for multi-axis servo system. The overall control system consists of three parts : the position controller, the disturbance observer with free parameters and cross-coupled controller which enhances contouring performance by reducing errors. Using two-degrees-of freedom conception, we design the command input response and the closed loop characteristics independently. The servo system can improve the closed loop characteristics without affecting the command input response. The characteristics of the closed loop system is improved by suppressing disturbance torque effectively with the disturbance observer. Moreover, the cross-coupled controller enhances tracking performance. Thus total position control performance is improved. Finally, the performance of the proposed controller shows that it improves the contouring performance along with the reference trajectory in the XY-table.

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A Study on the Design of Cross-Polarization Interference Canceler for Digital Radio Relay System with Co-Channel Dual Polarization (동일 채널 이중편파를 적용하는 디지털 무선 중계장치의 직교편파간섭제거기 설계에 관한 연구)

  • 서경환
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.13 no.3
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    • pp.225-236
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    • 2002
  • In this paper, to counteract a cross-polarization interference caused by co-channel dual polarization technique of digital radio relay system(DRRS), we analyze the theoretical model and digital design of cross-polarization interference canceller(XPIC). In addition a complex adaptive time domain equalizer(ATDE) is designed using a finite impulse response filter, and the structure of XPIC and its control method are also illustrated including ATDE. Our computer simulation shows that about 25 dB signature and more than 23 dB XPIC improvement factor can be obtained with XPIC and ATDE. In order to verify the operation of designed XPIC, we review the simulated results in view of tap number, algorithm convergence, system signature, and XPlC improvement factor in connection with 64-QAM DRRS with co-channel dual polarization.

A Comparative Study of Oswestry Back Pain Disability Questionnaire Versus Computer Adaptive Testing for Measuring Back Pain

  • Choi, Bong-Sam
    • Physical Therapy Korea
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    • v.20 no.4
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    • pp.22-31
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    • 2013
  • The aim of the present study was to compare measurement precisions of the Oswestry Back Pain Disability Questionnaire (ODQ) and a computer adaptive testing (CAT) method. The ODQ has been regarded as one of the most reliable condition-specific measure for back pain for decades. Cross-sectional study was carried out with two independent convenient samples from two out-patient rehabilitation clinics for back pain ($n_1=42$) and non-back pain group ($n_2=42$). Participants were asked to fill out the ODQ and CAT of International Classification of Functioning, Disability and Health-Activity Measure (ICF-AM). A series of Rasch analyses were performed to calculate person ability measures. The CAT measures had greater relative precision in discriminating the groups than did the ODQ measure in comparisons of the relative precision. The CAT measure appears to be more effective than did the ODQ measure in terms of measurement precision. By administering test items calibrated in a way, CAT measures using item response theory may promise a means with measurement precision as well as efficiency.